Wood surfacing machine



y 1942. R. M. BROWN 2,288,782

woon SURFACING MACHINE Filed Feb. 10, 1940 Y 2 Sheets- Sheet 1 ww MN v. wm Uww w mm w E E 2 H INVENTOR.

ATTORNEY;

R. M. BRO N 2,288,782

WOOD SURFACING MACHINE Fiied Feb. 10, 1940" Z Sheets-Sheet 2 @r T o Patented July 7, 1942 UNITED STATES ,PATE

NT OFFICE WOOD SURFAC'ING MACHINE Robert M. Brawn; Flint, Mich.

Application February 10, 1940, Serial No. 318,341

4 Claims. (Cl. 144-119) This invention relates to a machine primarily intended for the surfacing of bowling alleys, although it may be readily adapted for the sur-' facing of other types of floors or fiat areas, and has for its object to provide a machine which will very efficiently accomplish the rough surfacing and leveling of such surfaces, in addition, if desired, to accomplishing a further finishing or sanding of the said surfaces.

More particularly the said invention contemplates a surfacing machine incorporating therein a series of rotary cutters adaptedto sweep the surface of the work in a circular motion advancing to trace the spiral path, in which the paths of the individual cutters trace individual structure mounted on wheels II which I prefer and separate paths, although the path of one cutter, due to the width of such path, may, when so arranged, somewhat overlap the path of another individual cutter.

The invention also contemplates the tilting of the cutters to present only a portion of their edges to the work, and also contemplates the tilting of the said cutters in a direction or in directions calculated to determine a lead or a drag to that portion of the cutters edge presented to the work, as will become hereinafter more clearly apparent.

I Still further, it is an object of the invention to provide means, where thought necessary or desirable, whereby the machine will form its own.

self-leveling track in advance of the Wheels supporting the machine.

A still further object is to provide means whereby the surfacing cutters may be lifted out of engagement with the work throughout a part of their rotary sweeping motion when considered desirable.

Still further objects and advantages subsidiary to and resulting from the aforesaid objects or from the construction or operation of the invention as it may be carried into effect will become apparent as the said invention is hereinafter further disclosed.

In carrying the said invention into effect, I may provide the novel construction and arrangement of parts hereinafter described, by way of example, having reference to the accompanying drawings, wherein:

Figure 1 is an elevation, shown partly broken away and in section, of a machine embodying the said invention;

Figure 2 is an end elevation of the same;

Figure 3 is a plan of the same;

Figure 4 is a cross-sectional detail view of the cutter lifting cam and its support;

to arrange to travel along the marginal portions of the alley I2 although they may be positioned to travel along any suitably provided track. However, I contemplate having the machine form its own track on the margins of the alley by virtue of the operation of advance track cutters I3 arranged forwardly of the machine and over the said marginal portions of the alley to be surfaced. Where this arrangement is adopted I propose to first level, such as by hand,

a short length of the two marginal surfaces sufficient to accommodate the wheel base of the machine and thereby ensure the initial leveling of themachine; so that, as the said machine is thereafter moved forward along the alley, it will at all times be traveling on a continuing level track which is provided by the advance action of the forward track cutters l3.

The said track cutters l3 are shown as being operated by a motor l4 through any suitable gearing (not shown) in a gear box I5, and shafts l6 and IT, or other equivalent means. This motor is also shown asbeing adapted to drive the front wheels of the machine through the medium of pulleys l8 and I9 andthe belt 2|], to effect the required progress of the machine as a whole along the length of the alley; although, of course, the machine may be manually so moved forthe sake of convenience or of simplicity if so desired.

Intermediate of the length of the machine and forming part of the framework thereof are two largecircular tracks 2| and 22, one above the other and having a common axis, which .tracks respectively support rollers 23 and 24 mounted on the ends of spider arms 25 and 26 respectively. The upper spider arms 25 are attached to the lower spider arms 26 by connecting-members 21 so that all of the said arms may rotate about the said common axis as a unitary frame structure, which rotation of the arms on the said tracks is effected by a pinion 28 driven from the said motor l4 through suitable gearingin the said gear box It, the said pinionZBmeshing with a large circular rack 29 carried by the upper spider arms 25,

30 are more or less vertical spindles mounted in bearings 3i and 32 carried by the spider arms 25 and 26, respectively, and at least one of these bearings, that is the upper or the lower (in this case the lower bearing) is of an adjustable na ture, such as may be obtained by the incorporation therein of an eccentric bushing 33, for adjustment about the vertical axis of the other bearing of the spindle in such manner that the said spindle may be thrown slightly out of the true vertical position in any desired direction. Generally speaking, I prefer to tilt the said spindles inwardly at their lower ends toward the central main axis of the rotary spider arms, and where the direction of such tilting is definitely determined for a particular machine the spindle bearings may be fixedly mounted accordingly and the provision for further angular adjustment dispensed with.

The lower ends of the said spindles 39 are shown as being provided with disk cutters 34 which may be abrasive, toothed, or of any suitable cutting form according to the material and character of the work to be surfaced, these cutters being primarily intended to accomplish the rough cutting of the alley surface; and by the inclining of the cutters 34, through the tilting of their spindles 30 in the manner described, a portion of the edge of each cutter is presented to the work in a desirable manner. The upper ends of the spindles 30 are provided with pulleys 35 driven by belts 36, or such other suitable means from a motor 31 mounted above the said spider arms 25.

It will be readily seen that the main cutters 34 while revolving on their own individual axes are also caused to travel within the frame of the machine in a circular path about the vertical axis of the spider arms, this motion being effected by operation of the pinion 28 engaging the rack 29. Of course, if the machine were standing stationary, the tilted cutters would inscribe a circular groove on the work each cutter following in the path of the preceding cutter. However, when the machine is slowly moved steadily along the alley, as under the influence of the drive to the wheels II from the motor l4, each cutter then inscribes a groove of a slightly progressive spiral path on the work, and no two cutters will inscribe exactly the same path as will be an obvious geometric fact. Thus, by variation of the relative speeds of rotation of the spider arms and of forward progress of the machine as a whole, the character of the rough surfacing of the work may be varied and adapted to requirements.

It will also be seen, by reference to the diagram Figure 5, that the character of each individual cut may also be altered by varying the tilting of the spindles 30 of the cutters; so that if the said spindles be tilted directly towards the central vertical axis of the spider arms as illustrated in Figures 1 to 3, the outermost portions A of the cutters will engage the work, whereas if the said spindles are tilted in the direction indicated by the lines b in Figure 5, the points of contact of the cutters with the work will be at B. Similarly, if the direction of tilting be that of the lines 0, the point of contact of the cutters with the work will be at C. It will be observed that the character of the cut in each of these cases would differ due to a certain lead of the cutter in the case of 0, resulting in a somewhat wider out than in A, and also due to a certain drag of the cutter and a similarly wider cut as in B. Consequently the direction of tilting of the cutters may be determined to suit the character of cut desired or the nature of the material being worked. Furthermore, the individual cutters may be set at dissimilar angles where it would be of advantage .to so set them.

In some cases, especially where the machine is to be passed over the alley but once, or where it is being passed over alley for the last of several cycles, it may be desirable to definitely ensure that there will be no drag of the cutters 34 on the surface of the alley as the said cutters traverse the rearward part of their circular motion in the frame of the machine, and for such purpose I may mount the said spindles 30 for slight vertical movement in their bearings, and mount on each of the spider arms 26 a lever 38 the inner end of which engages a collar 39 on the adjacent spindle Bil and the outer end of which carries a roller 43 adapted to engage beneath a more or less semi-circular cam member ll circumscribing the rearward arc of the travel of the said rollers in the machine. This cam plate may thus depress the said rollers 49 when they are moving through such rearward arc and thereby cause the said levers to act on the collars of the said spindles 30 and thus raise the said spindles when they are moved through the rearward arc of their travel.

The cam plate is shown as being vertically adjustable on supports 42 so that it may be moved into or out of operative position, and wing nuts Q3 are provided for securing the cam plate in positions of adjustment.

id are guide rollers descending from the sides of the frame structure I to engage the sides of the alley for the purpose of guiding the machine down the length thereof as the work progresses.

t5 and 56 are conduits for the leads to the several motors, while t7 indicates any suitable type of current distributor or commutator to the rotating motor 31.

This invention may be developed within the scope of the following claims without departing from the essential characteristics of the said invention, and it is desired that the specification and drawings be read as being merely illustrative and not in the strictly limiting sense.

What I claim is:

1. In a wood surfacing machine of the type described, in combination, a main frame structure movable in a linear direction over a work surface, a plurality of circular track members having a common vertical axis in said frame, a sub-frame rotatable parallel to the work surface on said track members, a series of rotary cutters carried by said sub-frame and presented at an angle to the work, and means for rotating said cutters in said sub-frame and said sub-frame on said track members simultaneously.

2. In a wood surfacing machine of the type described, in combination, a main frame structure movable in a linear direction over a work surface, a plurality of circular track members having a common vertical axis in said frame, a sub-frame rotatable parallel to the work surface on said track members, a series of rotary spindles carried by said sub-frame, said spindles being capable of reciprocation in a generally vertical direction in said sub-frame, a series of rotary cutters carried by the lower ends of said spindles, means for rotating said spindles in said sub-frame and said sub-frame on said track members simultaneously and means for lifting said spindles in said sub-frame throughout a part of their circular movement therewith.

3. In a wood surfacing machine of the type described, in combination, a main frame structure movable in a linear direction over a work surface, a plurality of circular track members having a common vertical axis in said frame, a sub-frame rotatable parallel to the work surface on said track members, a series of rotary spindles carried by said sub-frame, said spindles being capable of reciprocation in a generally vertical direction in said sub-frame, a series of rotary cutters carried by the lower ends of said spindles, means for rotating said spindles in said subframe and said sub-frame on said track members simultaneously, spindle-raising levers carried by said sub-frame, and an arcuate cam operating said levers to raise said spindles throughout a part of their circular travel.

4. In a machine of the type described, in combination, a frame structure movable in a linear direction over a work surface, a series of elongated rotary spindles, a series of rotary cutters, each rigidly mounted on an end of a spindle, said spindles being presented at a tilted angle to the work, means for driving said spindles, and cutters on their own axis, means for simultaneously moving said spindles and cutters through a circular path which is parallel to the work surface and about a common vertical axis in said machine, means for positively adjusting the direction of tilting of the spindles relative to said vertical axis on changing the working faces of the cutters, and means for raising said outters out of contact with the work throughout a part of their circular movement.

ROBERT M. BROWN. 

